阅读说明：本技术 一种横向mimi格点阵等离激元共振吸收器 (Transverse MIMI lattice plasmon resonance absorber ) 是由 肖功利 杨文琛 薛淑文 杨宏艳 杨寓婷 张开富 李海鸥 于 2020-05-17 设计创作，主要内容包括：一种横向MIMI格点阵等离激元吸收器。由折射率为1.52的介质基底和以MIMI结构基本单元进行周期性排列形成的横向MIMI格点阵列构成,MIMI结构基本单元是由两列银长方体块和两列二氧化硅长方体块交替堆积形成,每列长方体块的长度和高度完全相同,垂直竖立在介质基底的上表面。整个结构放置在均匀的介质环境中,入射平面光波的入射方向即波矢k与介质基底的上表面垂直,入射光的电场方向平行于银长方体块和二氧化硅长方体块的长,入射光的磁场方向平行于银长方体块和二氧化硅长方体块的宽。通过两种不同的共振形式在吸收光谱上产生两个窄的共振吸收峰,且对介质环境折射率的变化具有很高的灵敏度,在生物化学物质检测领域具有很高的应用价值。(A lateral MIMI lattice plasmon absorber. The MIMI structure is composed of a dielectric substrate with the refractive index of 1.52 and a horizontal MIMI lattice point array formed by periodically arranging MIMI structure basic units, wherein the MIMI structure basic units are formed by alternately stacking two rows of silver cuboid blocks and two rows of silicon dioxide cuboid blocks, the length and the height of each row of cuboid blocks are completely the same, and the MIMI structure basic units are vertically erected on the upper surface of the dielectric substrate. The whole structure is placed in a uniform medium environment, the incident direction of incident plane light waves, namely the wave vector k, is vertical to the upper surface of the medium substrate, the electric field direction of the incident light is parallel to the lengths of the silver cuboid blocks and the silicon dioxide cuboid blocks, and the magnetic field direction of the incident light is parallel to the widths of the silver cuboid blocks and the silicon dioxide cuboid blocks. Two narrow resonance absorption peaks are generated on an absorption spectrum through two different resonance forms, and the method has high sensitivity to the change of the refractive index of the medium environment and has high application value in the field of biochemical substance detection.)

1. A lateral MIMI lattice plasmon absorber. By refractive index n₁The MIMI structure is characterized by comprising a dielectric substrate of 1.52 and a transverse MIMI lattice dot array formed by periodically arranging MIMI structure basic units, wherein the MIMI structure basic units are formed by alternately stacking two rows of silver and two rows of silicon dioxide cuboid blocks, are vertically erected on the upper surface of the dielectric substrate, and are arranged at a certain period along mutually vertical X-axis and Y-axis in the horizontal direction to form the transverse MIMI lattice dot array. The whole structure is placed in a uniform medium environment, incident light is plane wave, a light source is right above the whole structure, and the incident direction, namely a wave vector k, is vertical to the upper surface of the medium substrate. The transmitted light is emitted from the lower part of the MIMI lattice point array, the reflected light is emitted from the upper part of the MIMI lattice point array, and two narrow resonance absorption peaks are generated on an absorption spectrum through two different resonance forms.

2. The lateral MIMI lattice plasmon absorber of claim 1, wherein: each MIMI structure basic unit is formed by alternately stacking two rows of silver and two rows of silicon dioxide cuboid blocks, vertically erected on the upper surface of the dielectric substrate, and the height and the length of each row of cuboid blocks are equal.

3. A lateral MIMI lattice plasmon absorber according to claim 1 or 2, wherein: the height h of the silver cuboid blocks and the silicon dioxide cuboid blocks in each MIMI structure basic unit is between 100nm and 300nm, and the length a is between 100nm and 300 nm.

4. A lateral MIMI lattice plasmon absorber according to claim 1 or 2, wherein: width w of inner silver cuboid block₂The width w of the silver cuboid block at the outer side is between 10nm and 100nm₁The width d of the inner silicon dioxide cuboid block is between 10nm and 100nm₁The width d of the outside silicon dioxide cuboid block is between 10nm and 100nm₂Between 10nm and 100 nm.

5. The lateral MIMI lattice plasmon absorber of claim 1, wherein: the light source is arranged right above the whole structure, the incident direction, namely the wave vector k, is vertical to the upper surface of the dielectric substrate, the incident light wave is a TEM electromagnetic wave and is incident right above the whole structure, the magnetic field direction is parallel to the width of the silver cuboid blocks and the silicon dioxide cuboid blocks, and the electric field direction is parallel to the length of the silver cuboid blocks and the silicon dioxide cuboid blocks.

6. The lateral MIMI lattice plasmon absorber of claim 1, wherein: the MIMI structure basic units standing vertically on the upper surface of the dielectric substrate have an arrangement period D of 300 to 700nm in the width direction of the silver rectangular parallelepiped block and the silica rectangular parallelepiped block and an arrangement period T of 300 to 700nm in the length direction of the silver rectangular parallelepiped block and the silica rectangular parallelepiped block.

(I) technical field

The invention belongs to the technical field of micro-nano optics, and particularly relates to a lattice point array plasmon resonance absorber which is formed by alternately stacking two rows of silver nano cuboid blocks and two rows of silicon dioxide nano cuboid blocks and takes a transverse MIMI as a basic structural unit.

(II) background of the invention

With the continuous development and progress of micro-nano optical and microelectronic processing technologies, surface plasmons have attracted the attention of more and more researchers, and are generally described as surface waves formed by collective oscillation of free electrons on a metal surface, which are strongly bound to the metal surface and propagate on the metal surface, generated at a metal-medium interface, and the optical field intensity of the surface waves is maximum at the interface and is exponentially attenuated along a direction perpendicular to the interface. This phenomenon can overcome the bottleneck that conventional optics suffers from the diffraction limit of light, because it can control light in a very small nanometer size range, which plays a crucial role in the development of integrated photonic devices, all-optical communication, biosensing, biomedicine, new energy and other fields. With the continuous development and maturity of various micro-nano processing and structure representation technologies, researchers can easily prepare and represent various complex metal nano structures experimentally, except for designing a plurality of high-performance photoelectric devices based on surface plasmons on theoretical calculation and numerical simulation. The basic principle of the metal structure is revealed by researching the properties of surface plasmons in the metal structure, and new application fields are continuously discovered, so that the development trend of the surface plasmons is reached.

Various forms of surface plasmon excitation have been developed in continuous research over the last decade, especially by means of plasmon lattice resonance (SLRs) technology in plasmonics, because the electromagnetic field properties associated with one nanoparticle in SLRs can play a role in influencing the response of neighboring nanoparticles, and can significantly improve the quality factor and spectral properties of localized plasmon resonance. People have made various biochemical sensors with high sensitivity, miniaturization and rapid response by utilizing the sensitivity of the sensor to medium environment and the enhancement of local field, and the sensor is widely applied to the field of biological sample and chemical substance detection.

In recent years, many absorbers based on plasmon lattice point resonance are proposed and researched, and the invention patent provides a transverse MIMI lattice point array plasmon resonance absorber which has very high quality factor and absorption coefficient compared with other absorbers based on plasmon, more importantly, the transverse MIMI lattice point array plasmon resonance absorber generates two absorption peaks on an absorption spectrum through two different resonance excitation forms OLP and ILP in SLRs under normal incident plane light waves, can well realize static tuning by changing the geometric parameters of basic structural units, has very high sensitivity to a medium environment, and has very high application value in the field of biochemical sensing.

Disclosure of the invention

The invention aims to design a transverse MIMI lattice plasmon resonance absorber, further study the influence of geometrical parameters and medium environment on the resonance absorption peak of the absorber on the basis of the original structure, and continuously search and explore the application value of the absorber in the fields of sensing, communication and the like. By changing the height, length, width and other dimensions of the silver nano cuboid blocks and the silicon dioxide cuboid blocks, the refractive index of the medium environment and other parameters, the structure can be found to be capable of effectively adjusting the properties of the transverse MIMI lattice plasmon resonance absorber, such as absorption coefficient, quality factor, resonance wavelength and the like.

The invention designs a transverse MIMI lattice point array plasmon resonance absorber which mainly comprises a dielectric substrate and MIMI cuboid blocks with periodic arrangement, wherein the MIMI cuboid blocks are formed by alternately and transversely stacking two silver cuboid blocks and two silicon dioxide cuboid blocks into a group to form a MIMI basic unit, the length and the height of each column of cuboid blocks are completely the same and are vertically erected on the upper surface of the dielectric substrate, each MIMI basic unit is distributed on the upper surface of the dielectric substrate along the X axis and the Y axis which are horizontally vertical to each other in the same periodic arrangement to form a transverse MIMI lattice point array, the whole structure is placed in a uniform dielectric environment, the incident light is a plane wave, the light source is right above the whole structure, the incident direction, namely the wave vector k, is vertical to the upper surface of the dielectric substrate, and the electric field direction of the incident light is parallel to the length of the silver cuboid blocks and the length of the silicon dioxide cuboid blocks. The transmitted light emerges from below the MIMI lattice point array and the reflected light emerges from above the MIMI lattice point array.

The height of the silver cuboid blocks and the height of the silicon dioxide cuboid blocks in each MIMI basic unit can be any height which meets the working condition of the transverse MIMI lattice plasmon absorber, and in order to obtain the optimal characteristics, the heights of the silver cuboid blocks and the silicon dioxide cuboid blocks are both 180 nm.

The lengths of the silver rectangular parallelepiped block and the silica rectangular parallelepiped block in each MIMI basic unit may be any lengths that meet the operating conditions of the lateral MIMI lattice plasmon absorber, and in order to obtain the optimum characteristics, the lengths of the silver rectangular parallelepiped block and the silica rectangular parallelepiped block are used as 230 nm.

The width of the outer silver cuboid blocks in each MIMI basic unit can be any width meeting the working condition of the transverse MIMI lattice plasmon absorber, and in order to obtain the optimal characteristics, the width of the outer silver cuboid blocks is 40 nm.

The width of the inner silver cuboid blocks in each MIMI basic unit can be any width meeting the working condition of the transverse MIMI lattice plasmon absorber, and in order to obtain the optimal characteristics, the width of the inner silver cuboid blocks is 40 nm.

The width of the outer silica rectangular parallelepiped block in each MIMI basic cell may be any width that meets the operating conditions of the lateral MIMI lattice plasmon absorber, and in order to obtain the optimum characteristics, the outer silica rectangular parallelepiped block width is adopted to be 50 nm.

The period of the transverse MIMI lattice point array can be in any accordance with the period of the working condition of the transverse MIMI lattice point plasmon absorber, and in order to obtain the optimal characteristic of the absorber, the periods of the transverse MIMI lattice point array along the length direction and the width direction of the silver cuboid blocks and the silicon dioxide cuboid blocks in each MIMI basic unit are 400 nm.

The medium substrate material can be any material which meets the working condition of the transverse MIMI lattice plasmon absorber, and in order to obtain the optimal characteristic of the absorber, the refractive index n is used₁Medium of 1.52 is base material, and the lateral MIMI lattice point is formedThe array plasmon resonance absorber is placed in air or vacuum.

Compared with the existing plasmon absorber, the invention has the advantages that: 1. under the excitation of normal incident flat light wave, the transverse MIMI lattice plasmon resonance absorber has two resonance absorption peaks on the absorption spectrum, which are generated by two excitation forms of OLP and ILP, respectively, so that when the absorber is applied to the sensing field, the application range of light source bandwidth can be enlarged and higher sensing accuracy can be provided 2. by changing the geometric parameters of the silver cuboid block and the silicon dioxide cuboid block and the refractive index n of the medium environment₂The wavelength, bandwidth, absorbance and quality factor of the two resonant absorption peaks can be statically changed. 3. Two resonance absorption peaks on the absorption spectrum have very high quality factors, and the wavelengths of the two resonance absorption peaks follow the refractive index n of the medium environment₂Compared with other plasmon absorbers, the transverse MIMI lattice plasmon absorber has the characteristic that the resonance wavelength can be flexibly adjusted from visible light to near infrared band. 5. Because the same period exists in the X-axis direction and the Y-axis direction, each MIMI basic unit has a simple structure and has the characteristic of easy processing.

(IV) description of the drawings

Fig. 1 is a schematic diagram of a three-dimensional structure of the transverse MIMI lattice plasmon absorber.

Fig. 2 is a schematic diagram of a two-dimensional structure XZ surface of each MIMI elementary cell of the present lateral MIMI lattice plasmon absorber.

Fig. 3 is a schematic view of the two-dimensional structure YZ plane of each MIMI elementary cell of the present lateral MIMI lattice plasmon absorber.

Fig. 4 is a schematic diagram of a two-dimensional structure XY surface of each MIMI elementary cell of the present lateral MIMI lattice plasmon absorber.

FIG. 5 is three spectrograms of reflection, transmission and absorption obtained when the present transverse MIMI lattice plasmon absorber works optimally.

Fig. 6 is an absorption spectrum of the present lateral MIMI lattice plasmon absorber obtained when the length a of the silver rectangular parallelepiped block and the silicon dioxide rectangular parallelepiped block in each MIMI basic unit is changed in the range of 170nm to 230 nm.

Fig. 7 is an absorption spectrum of the present lateral MIMI lattice plasmon absorber obtained when the height h of the silver rectangular parallelepiped block and the silica rectangular parallelepiped block in each MIMI basic unit is changed in the range of 180nm to 240 nm.

FIG. 8 is a drawing showing the width w of the inner rectangular parallelepiped block of silver in each MIMI basic cell₂The absorption spectrum of the transverse MIMI lattice plasmon absorber is obtained when the wavelength is changed within the range of 30nm to 60 nm.

FIG. 9 is a diagram showing the width d of the inside rectangular parallelepiped block of silicon dioxide in each MIMI basic cell₁The absorption spectrum of the transverse MIMI lattice plasmon absorber is obtained when the wavelength is changed within the range of 40nm to 70 nm.

FIG. 10 shows the present MIMI lattice plasmon absorber placed in different medium environments n₂And (3) an absorption spectrum graph of the transverse MIMI lattice plasmon absorber obtained in the range of 1.0-1.4.

(V) detailed description of the preferred embodiments

The invention is further explained below with reference to the drawings and the present embodiment:

fig. 1 is a schematic three-dimensional structure diagram of the transverse MIMI lattice plasmon absorber. Comprising a refractive index n₁The dielectric substrate 5 may have a thickness of 1.52, which satisfies the operating conditions, and 1 and 3 are the outer silver cuboid blocks and the inner silver cuboid blocks, respectively, in the MIMI basic unit, and 4 and 2 are the outer silica cuboid blocks and the inner silica cuboid blocks, respectively, in the MIMI basic unit. The incident light is a plane wave, the wave vector k is parallel to the Z axis and vertically and positively enters the transverse MIMI lattice plasmon absorber along the negative direction, the polarization direction (electric field direction) of the incident light is perpendicular to the wave vector k and parallel to the Y axis in the XZ plane, and the magnetic field direction is parallel to the X axis.

FIG. 2 is a schematic diagram of the XZ plane of the two-dimensional structure of each MIMI basic unit of the MIMI lattice plasmon absorber, which works optimally, wherein the period of each MIMI basic unit arranged above the dielectric substrate along the X-axis direction is 400nm, and the outer silver rectangular isThe width of the block 1 is w₁40nm, the width of the inner silver cuboid block 3 is w₂The outer rectangular silica block 4 had a width d of 40nm₂50nm, and the width d of the inner rectangular silica block 2₁The whole structure is vertically arranged on the upper surface of the dielectric substrate in a standing way, namely 50 nm.

Fig. 3 is a schematic view of the YZ plane of the two-dimensional structure of each MIMI basic unit of the present lateral MIMI lattice plasmon absorber, which works best, wherein the period of each MIMI basic unit arranged above the dielectric substrate along the Y-axis direction is 400nm, and the height of each of the silver rectangular parallelepiped block and the silica rectangular parallelepiped block is 180 nm.

Fig. 4 is a schematic two-dimensional structure XY-plane diagram of each MIMI basic unit of the present lateral MIMI lattice plasmon absorber, and when the operation is optimal, the lengths of the silver rectangular parallelepiped block and the silica rectangular parallelepiped block are both a ═ 230 nm.

When the invention works: the polarization direction (electric field direction) of the incident planar light wave is parallel to the Y axis in the XZ plane, the magnetic field direction is parallel to the X axis, and the wave vector direction k is parallel to the Z axis and is positively incident along the Z axis negative direction. Incident planar light waves can simultaneously excite plasmon lattice point resonances of two types of electric dipoles and four dipoles in the transverse MIMI lattice point array, two different strong resonance coupling effects can be generated between two adjacent silver cuboid blocks, two different specific absorption peaks can be generated for incident light under specific structural parameters, and the planar light waves have high quality factors and absorption coefficients compared with other periodic array-based plasmon absorbers. The structure parameters of the silver cuboid blocks and the silicon dioxide cuboid blocks are changed or the transverse MIMI lattice plasmon absorber is placed in different medium environments, so that the offset and the absorption coefficient of two resonance absorption peaks can be changed, and the characteristic can be utilized to realize the static tuning of the transverse MIMI lattice plasmon absorber or the application of the transverse MIMI lattice plasmon absorber in the fields of chemical substance detection and biosensing. FIG. 5 is a spectrum diagram of the transverse MIMI lattice plasmon absorber with optimal operation, wherein the abscissa represents the wavelength of incident plane light and the ordinate represents the reflection coefficient, transmission coefficient and absorption coefficient of incident plane lightAnd the three curves respectively represent a reflection spectral line R (reflectance), a transmission spectral line T (transmittince) and an absorption spectral line A (absobance) of the transverse MIMI lattice plasmon absorber on incident plane light waves, and the relationship of the reflection spectral line R (reflectance), the transmission spectral line T (transmittince) and the absorption spectral line A (absobance) is A1-T-R. As can be seen from absorption spectral lines, the two absorption peaks of the transverse MIMI lattice plasmon absorber have very narrow bandwidths and are respectively positioned at lambda₁790nm and λ₂1124nm, both absorption peaks have a very high quality factor and are at λ₁The absorption coefficient of the resonance absorption peak at 790nm is as high as 0.94.

The present invention has been made in view of the above-mentioned circumstances, and it is an object of the present invention to provide a method for manufacturing a MIMI cell, which comprises the steps of performing development under fixed configuration parameters and initial values, ① obtaining an absorption spectrum result as shown in fig. 6 when the length a of each of the silver rectangular parallelepiped blocks and the silica rectangular parallelepiped blocks in each MIMI basic cell is changed within a range of 170nm to 230nm, ② obtaining an absorption spectrum result as shown in fig. 7 when the height h of each of the silver rectangular parallelepiped blocks and the silica rectangular parallelepiped blocks in each MIMI basic cell is changed within a range of 170nm to 240nm, ③ obtaining an absorption spectrum result as shown in fig. 7 when the width w of the inner silver rectangular parallelepiped block in each MIMI₂The results of the absorption spectrum obtained when the MIMI basic unit is changed in the range of 30 to 60nm are shown in FIG. 8, ④ the width d of the inner rectangular silica block in each MIMI basic unit₁The absorption spectrum results obtained when the absorber is changed in the range of 40 nm-70 nm are shown in FIG. 9, ⑤ when the transverse MIMI lattice plasmon absorber is placed in n₂Fig. 10 shows the absorption spectrum results obtained when the samples were placed in different medium environments of 1.0 to 1.4.

In combination with the embodiment, the following results are obtained through simulation verification of the transverse MIMI lattice plasmon absorber:

fig. 6 is an absorption spectrum obtained when the length a of the silver rectangular parallelepiped block and the silicon dioxide rectangular parallelepiped block in each MIMI basic unit is changed in a range of 170nm to 230 nm. The abscissa of the graph represents the incident wavelength of the plane light, and the ordinate represents the absorption coefficient of the incident plane light wave, and four different sets of absorption spectra curves in the graph are respectively the silver cuboid block and the silicon dioxide length in each MIMI basic unitAs a result of simulation of the cube blocks having different lengths, the lengths a were 170nm, 190nm, 210nm, and 230nm, respectively. As can be seen from the results in the figure, as the length a increases, both absorption peaks of the present lateral MIMI lattice plasmon absorber gradually red-shift, and the absorption coefficient of the left absorption peak gradually increases from 0.84 to 0.94, the formant wavelength λ is increased₁Increasing from 688nm to 760 nm. The absorption coefficient of the right absorption peak is slowly reduced from 0.38 to 0.34, and the wavelength lambda of the resonance peak is₂Increasing from 894nm to 1124 nm.

Fig. 7 is an absorption spectrum obtained when the height h of the silver rectangular parallelepiped block and the silica rectangular parallelepiped block in each MIMI basic unit is changed within a range of 180nm to 240 nm. The abscissa and ordinate in the figure are the same as those in fig. 6, and four different sets of absorption spectrum curves in the figure are simulation results for different heights of the silver rectangular parallelepiped block and the silicon dioxide rectangular parallelepiped block in each MIMI basic cell, respectively, and the heights h thereof are 180nm, 200nm, 220nm, and 240nm, respectively. As can be seen from the results in the figure, as the height h increases, the absorption peak at the left of the present lateral MIMI lattice plasmon absorber gradually red-shifts, and the absorption coefficient of the left absorption peak gradually decreases from 0.94 to 0.75, the formant wavelength λ₁Increasing from 760nm to 840 nm. While the absorption peak on the right is slightly blue-shifted and the absorption peak hardly changes.

FIG. 8 is a drawing showing the width w of the inner rectangular parallelepiped block of silver in each MIMI basic cell₂Absorption spectra obtained when the wavelength was varied from 30nm to 60 nm. The abscissa and ordinate of the graph are the same as those of fig. 6, and four different sets of absorption spectra curves in the graph are simulation results of different widths of the inner silver cuboid blocks in each MIMI basic cell, respectively, and have a width w₂Respectively 30nm, 40nm, 50nm and 60 nm. As can be seen from the results in the figure, with the width w₂The two absorption peaks of the transverse MIMI lattice plasmon absorber are gradually blue-shifted, the absorption coefficient of the absorption peak on the left side is increased and then reduced, the absorption coefficient is increased from 0.85 to 0.97 and then reduced to 0.76, and the resonant peak wavelength lambda is₁Decreasing from 790nm to 738 nm. The absorption coefficient of the right absorption peak is gradually reduced from 0.44 to 0.15, and the wavelength lambda of the resonance peak is₂Decreasing from 1150nm to 1104 nm.

FIG. 9 is a diagram showing the width d of the inside rectangular parallelepiped block of silicon dioxide in each MIMI basic cell₁Absorption spectra obtained when the wavelength was varied from 40nm to 70 nm. The abscissa and ordinate of the graph are the same as those of FIG. 6, and four different sets of absorption spectra curves in the graph are simulation results for different widths of the inside rectangular silica blocks in each MIMI basic cell, respectively, and have a width d₁40nm, 50nm, 60nm and 70nm respectively. As can be seen from the results in the figure, with the width d₁The two absorption peaks of the transverse MIMI lattice plasmon absorber gradually blue-shift, the absorption coefficient of the left absorption peak gradually decreases from 0.95 to 0.75, and the resonance peak wavelength lambda is₁Reduced from 782nm to 736 nm. The absorption coefficient of the right absorption peak is gradually increased from 0.29 to 0.38, and the wavelength lambda of the resonance peak is₂Reduced from 1158nm to 1088 nm.

FIG. 10 shows the present MIMI lattice plasmon absorber placed in different medium environments n₂And (3) an absorption spectrum graph of the transverse MIMI lattice plasmon absorber obtained in the range of 1.0-1.4. The representation of the abscissa and the ordinate in the figure is the same as that in fig. 6, four groups of different absorption spectrum curves in the figure are respectively simulation results of the transverse MIMI lattice plasmon absorber when the transverse MIMI lattice plasmon absorber is placed in different medium environments, and the refractive index n of the medium environment is the same as that of the medium environment₂1.0, 1.1, 1.2, 1.3 and 1.4 respectively. As can be seen from the results in the figure, the refractive index n with the medium environment₂The absorption coefficient of the left absorption peak is gradually reduced from 0.94 to 0.68, and the resonance peak wavelength lambda is gradually reduced to the absorption coefficient of 0.68₁Increasing from 760nm to 860 nm. The absorption coefficient of the right absorption peak is gradually reduced from 0.35 to 0.07 and is nearly disappeared, and the wavelength lambda of the resonance peak₂Increasing from 1124nm to 1268 nm. The two absorption peaks have strong sensitivity to the change of the medium environment refractive index and good linearity, and the left side lambda is₁The degree of sensitivity of the absorption peak to the ambient refractive index of the medium is up to 261nm/RIU, and the right side lambda₂Absorption peak of the light beam refracts medium environmentThe sensitivity of the rate is as high as 230 nm/RIU. The characteristic has high application value as a high-sensitivity sensor in the field of biochemical substance detection, and particularly has two absorption peaks with high quality factors, so that the accuracy of a detection result can be well improved, and the requirement on the bandwidth of incident plane light waves can be reduced.

The above embodiments are merely illustrative of the technical solutions and purposes of the present invention, and are not intended to limit the present invention, and any modifications, equivalents, improvements, etc. made within the scope of the disclosure of the present invention should be included in the protection scope of the present invention for those skilled in the art.